The population of children in foster care has nearly doubled in the past decade and grown more troubled and younger in age, while services to these youth and their families have become scarcer. Given their significant histories of maltreatment separation, and loss. these children are at risk for long-term psychosocial maladjustment. A central premise of this proposal is that much is now known about the early development of emotional and behavioral problems., and that it is feasible to develop and implement effective family-based preventive interventions for younger foster children that target antecedents. Based on a successful pilot study a larger scale randomized efficacy trial of the OSLC Early Intervention Foster Care Program (EIFC) is proposed. The EIFC program is a developmentally downward extension of the theory-based, empirically evaluated Multidimensional Specialized Foster Care program. The EIFC preventive intervention targets 4 co-occurring conditions in maltreated preschoolers in foster care: (1) behavioral problems; (2) attachment; (3) emotion dysregulation; and (4) developmental delays. In the proposed study, we will gather data from a 180 four-year-old children, 120 of whom are in the Oregon foster care system. Another 60 same-aged children living with their biological families will be included in a community comparison sample (CC). Foster children will be randomly assigned to either the EIFC experimental 12-month intervention condition (n=60) or a Regular Foster Care Condition (RFC; n=60). In the EIFC condition, four parenting strategies will be targeted: () consistent and teaching-oriented discipline, (2) sensitive responding to the child's cues, (3) monitoring and supervision of the child, and (4) positive reinforcement. Daily parenting practices are expected to mediate changes in child adjustment. The EIFGC program will also work with and collect data from biological parents and adoptive parents with whom children will be placed following discharge from the program. In contrast to the EIFC condition, in the RFC condition, it is expected that lower rates of positive reinforcement by the foster parents, resulting in deterioration of child adjustment and increasing the risk of disrupted placements as well as more negative outcomes in subsequent placements. Multiple assessments will be conducted over a 24 month period, allowing for examination of the immediate effects of the intervention as well as how children who have received the intervention fare in the transition to elementary school.